Proteolytic Disassembly of Viral Outer Capsid Proteins Is Crucial for Reovirus-Mediated Type-I Interferon Induction in Both Reovirus-Susceptible and Reovirus-Refractory Tumor Cells

Figure 3

Effects of inhibition of cathepsins B and L on reovirus-mediated induction of IFN-β and Noxa in tumor cells. (a), (b) mRNA levels of IFN-β and Noxa following reovirus or ISVP infection in the cells pretreated with cathepsin inhibitors. Cells were preincubated for 1 hr in the medium supplemented with 10 μM of inhibitors of cathepsins B and L. Cells were infected with reovirus or ISVP in equivalent doses for an MOI of 20. Data were normalized by the data of the nopretreatment/reovirus group. (c) mRNA levels of IFN-β and Noxa following transfection with the reovirus genome (200 ng/mL) and 5′-ppp dsRNA (1 μg/mL). Cells were harvested for the evaluation of IFN-β and Noxa mRNA levels by qRT-PCR analysis following a 24-hour incubation. Data were normalized by the data of the nopretreatment/reovirus genome group. The data shown represent the mean ± SD of triplicate measurements. Cts, cathepsin. , , compared with the nopretreatment/reovirus or reovirus genome group.

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